Breathing apparatus



May 8, 1923.

F. w. KoEHLER BREATHING APPARATUS Filed Maron 29, 1921 3 sheets-sheet l A TTOR/VEYS May 8, 1923.

F. W. KOEHLER BREATHI NG APPARATUS lFiled March 29,

1921 3 Sheets-Sheet 2 m 8 E m W FREDERICK W. KOEHLER, F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO Armes CORPORATION, or PITTSBURGH, PENNSYLVANIA, A ooRro'rIon or YORK.

BREATHING APPARATUS.'

Application filed March 29, 1921. Serial No. 458,576.

To all lwhom t may concern.'

Be it known that I FREDERICK W. Konn- LER, a citizen of the nited States and res1- dent of Pittsburgh, county of llegheny, State of Pennsylvania, have invented certain new and useful Improvements in Breathing Apparatus, of which the followingis a specification.

y invention relates to breathing apparatus of the type which includes a tubular breathing mask and has for its object to provide a novel arrangement whereby it is possible to use a conducting hose of increased length and thereby increase the range of the apparatus without materially increasing the breathing effort of the wearer of the mask. A further object of the invention is to provide a gas or respiration mask of the type adapted to protect the eyes and respiratory organs and passages of the wearer from the eects of injurious gases and the like, which is arranged so as to give unimpaired vision, is comfortable to wear, and is highly efficient for its intended purpose and in which the factor of safety is very highly developed. Other more specific objects of my invention will appear from the description hereinafter and the features of novelty will be pointed out in the appended claim.

In the accompanying drawings which illustrate an example of my invention without defining its limits, Figure 1 is a view illustrating my improved mask in position on the wearer; Fig. 2 is a rear view of the mask; Fig. 3 is a side elevation of the breathing fixture; Fig. 4 is a similar view looking in a. direction at right angles to Fig. 3; Fig. 5 is a lan view of said fixture; Fig. 6 is a sectional) elevation thereof on the line 6-6 of Fig. 5; Fig. 7 is a view similar to Fig. 4, with parts omitted to show the interior arrangement; Fig. 8 is a horizontal section on the line 8 8 of Fig. 6; and Fig. 9 is a view illustrating the complete apparatus arranged according to my invention and including my improved mask.

As illustrated in the drawings, the mask comprises a flexible face covering 10 which may be of any usual form and constructed of any suitable material and which is provided in the customary way with head straps 1l whereby the mask is fixed in operative position upon the wearer; the mask includes further the customary eye pieces 12 which may also be of any conventional form and arrangement. The face covering 10 is connected with the breathing fixture 13 which, in turn, communicates withthe hose 14; the latter may be connected either with an airpurifying apparatus or with the atmosphere at some distant point where the air is free from the noxious gas against which the mask is worn as a. protection or said hose, when of increased length, may be connected with an oxygen tank, as shown in Fig. 9, and as will be more fully referred to hereinafter. The breathing fixture 13 is rovided with a partition 15 whereby said xture is divided intoA two separate and independent chambers 16 and 16, as shown in Fig. 6, the chamber 16 being an inhalation chamber in communication with the hose 14 at one end, and at its other end being provided with a tubular extension 17 which extends into a Hexible member 18.v The latter, as shown in Fig. 2, preferably diverges outwardly and is dimensioned and positioned so as to lie over the nose of the wearer and thus separate theeyes from the nostrils and the mouth, when the mask is worn in operative position. An annular valve seat 19 is located in the chamber 16 for co-operation with an inwardl movable disk valve 20 to control communication between the hose 14 and the flexible member 18, and consequently between the air-purifying apparatus or the atmosphere and the interior of the gas mask. The inward movements of the disk valve 20 away from the seat 19 may be limited or arrested by means of a spider 21. The chamber 16u of the breathing fixture 13 is an exhalation chamber and communicates with the interior of the gas mask and with the atmosphere by means of a tube 22 which, as shown in Fig. 6, extends into the chamber 16a and also outwardly beyond the same in a direction transverse to the major axis of the fixture 13. Communication between the interior of the chamber 16@L and the atmosphere is controlled by means of a disk valve 23 preferably made of mica or some other relatively smooth material and cao-operating with a valve seat 24 located in the tube 22 and preferably constructed in the form of a knife edge, as shown in Fig. 6.l The disk valve 23 is maintained upon and returned to the seat 24 by means of a spring 25 which bears with one end against the valve 23 and with its other end against a spider 26 to which said other end is preferably secured,

ERICN said spring bei'ng extremely sensitive, yet

inhales, the disk valve 20 will be lifted from the seat 19 by the suction effect of the inhalation, which is also exerted upon the disk valve 23 to draw the same against its seat' and thereby augment the action of the spring to seal the interior of the mask against the entrance of any of the noxious gases; as the disk valve 20 is lifted from its seat, a supply of fresh, pure air is drawn through the inhalation chamber 16 and tubular extension 17 into the flexible. memvber 18 and from thence into the interior of -the mask.

As the wearer of the mask exhales, the pressure of the exhalation will press the disk valve 20 firmly against its seat 19, thereby sealing the fresh air inlet while at the same time the force of said exhalation will move the disk valve 23 away from its seat 24 against the pressure of the spring 25 to permit the exhaled air to escape from the interior of the mask through the exhalation chamber 16a to the atmosphere.

' Because of the knife-edge form of the seat 24, a minimum of surface is presented u-pon which foreign matter may lodge to destroy or interfere with the sealing'v effect of the valve 23 by causing an imperfect seating thereof and thereby permit the entrance of the noxious gases.. As these gases have a tendency to seep through even the smallest openings, it is essential to the safety of the wearer of the mask that a perfect seal be maintained between the seat 24 and the valve 23. This is assured in the present construction because of the knife-edge form of said seat and also because of the relatively smooth surface of the valve 23 which, as hereinbefore stated, is preferably made of mica and therefore is not likely to become a lodgment for foreign matter whereby the efficiency of the seal might be destroyed.

In many instances it is desirable, because of the nature of the work to be accomplished and in order to maintain a maximum freedom of movement, not to burden the laborer with any more apparatus than is absolutely necessary. At the same time, in such cases, it sometimes happens that the point atl which fresh, pure air is available is located at such a distance from the scene of operations as to require the use of a conducting hose 14 of increased length. A considerable resistance to the flow of air is.how ever, developed in the long hose which requires a considerable edort to overcome and thus makes it difiicult and ofttimes impossible for the wearer of the mask to breathe.

Lacasse -\tween the tank 32 and the reducing valve 31 and another valve 34 serving toclose the exit `end of said tank 32 in the customary manner.

In practice, the pressurev in the vtank 32 may be approximately 150 atmospheres which is reduced by the reducing valve 31 to approximately 6 atmospheres; the action of the oxygen in .passing through the injector 229il at this reduced pressure draws the air inwardly through the air inlet 29 and then propels the mixture of air and oxygen lengthwise of and through the hose 14 to the interior of the mask. It will be understood that the action is such as to set the mixture of airA and oxygen in motion with just enough speed to cause it to move lengthwise of the hose without any assistance from the wearer of the mask and without generating a pressure or developing any other action in the interior of said mask suflicient to disturb .the disk valve 23. Furthermore, .the action of the moving mixture of air and oxygen isnot such as to prevent the closure of the'disk valve 20 whenfthe wearer4 of the mask exhales. In other words, the intended operation of, the mask elements, as previously explained herein, is not interrupted or interfered with while at the same time,l with the described arrangement, a condition is produced inside of said mask which very closely approaches and is only slightly above atmospheric pressure and which4 adds nothing to the normal effort of breathing even though the hose 14 is from one hundred to one hundred and twenty-five feet in length. Ordinarily, it is difficult, if not impossible, for the wearer of a mask to breathe if the conducting hose is more than twentyfive feet in length. In addition to its other advantages, the arrangement set forth in'- cludes the additional advantage of raising I the oxygen content in the air just enough to provide a highly vitalized breathing mixture to the wearer of the mask.

With the described a paratus the range of operation is increase to a maximum extent and the laborer wearing the mask is burdened to a minimum degree and at the same time his freedom of movement is not interfered with. This makes it possible to labor with a minimum of e'ort and to accomplish a maximum amount of work in a given time, thereby increasing the etliciency of the laborer to a material extent.

It will be understood that, While it is preferable to utilize my improved mask in the apparatus illustrated in Fig. 9, said mask may be replaced by tubular breathing masks of dilerent construction and arrangement. In any case, the improved apparatus is easily attached to an oxygen tank of common form and in practice utilizes the pressure of the oxygen itself as a propelling medium for sup lying the interior of the mask'with a v1ta izing breathing mixture through a relatively long conducting hose.

My improved apparatus and mask are extremely simple in construction and arrangement, the mask providing a maximum of safety for the wearer, being comfortable to wear and at the same time being easily adjusted in position.

Various changes in the specific form shown and described may be made within the scope of the claim without departing from the spirit of my invention.

` I claim:

A gas mask comprising a face covering, a

breathing fixture carried thereby and having interior inhalation and exhalation chambers independent of each other, a flexible member within said face covering connected with said inhalation chamber and arranged to lie over the nose of the wearer, a hose connected with said inhalation chamber, a valve seat in said inhalation chamber, an inwardly opening valve co-operating with said seat to control the communication between said hose and said inhalation chamber, a tube extending into the exhalation chamber and outwardly beyond the same, an annular knife-edge seat in said tube, an outwardly opening disk valve co-operating with said seat to seal said tube and to permit the escape of exhaled air therethrough, a spider located in registry with sai-d annular seat, a spring bearing against said valve with one end and having its other end secured to said spider and an apertured cap fixed upon the outer end of said tube to protect said disk valve and its seat against injury.

In testimony whereof I have hereunto set my hand.

FREDERICK W. KOEHLER. 

